Rotary flow dust separators

Mechanism and Type of Rotary Flow Dust Separators... 

The principles of fluidisation, discussed in Chapter 6, are applied in this type of dryer, shown typically in Figure 16.25. Heated air, or hot gas from a burner, is passed by way of a plenum chamber and a diffuser plate, fitted with suitable nozzles to prevent any back-flow of solids, into the fluidised bed of material, from which it passes to a dust separator. Wet material is fed continuously into the bed through a rotary valve, and this mixes immediately with the dry charge. Dry material overflows through a downcomer to an integral after-cooler. An alternative design of this type of dryer is one in which a thin bed is used. 

To separate particles from gaseous streams, cyclones are frequently used in large-scale practices. In fact, cyclone based dust collectors are one of the most widely used devices for removing larger-sized particles. Virtually all cyclones used industrially are reverse-flow cyclones. There are two other types of cyclones rotary-flow (CiUberti and Lancaster, 1976a, b) and uniflow (Ter Linden, 1949). Only the reverse-flow cyclone will be considered here. 

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